AT&T's "4G" is slower than T-Mobile's, but where I live the only data service T-Mobile provides is EDGE or just plain 2G, hence why I would rather have AT&T. Where I am in Maine right now I get about 80kbps download and about 60kbps upload on T-Mobile. Using the prepaid tablet plan on AT&T in the same location I got 2-3Mbps download and about 800kbps upload. Determining which carrier's data speeds are faster greatly varies depending on your location. I just thought I would try to help some people out that are in a place where T-Mobile has terrible/no service and they don't want to pay $60 a month for the prepaid smartphone plan from AT&T. This tablet plan is half the price. To make calls you can just use Groove IP along with Google Voice, and that is through your data. So you no longer need a phone plan, only data!!
Nexus 4 Limbo Level 3 Survivor